** Steganography

*** Introduction

Steganography is to hide data in images (or different types of files), can be
hidden, for example:

- Source code.
- List of compromised servers, and devices.
- Plans for future attacks.
- And everything that you can think of.

*** Methods for hiding information

**** Least Significative Byte

The rightmost bist that makes up an image, is called the least significative
byte (LSB), they can be modified without a change in the appearance of the
image.

**** Masking

This technique modifies the image, it is mostly used with grayscale images, or
noisy pictures like the sea, and the information will be store in those parts,
actually modifying the image.

**** Algorithms and Transformations

This technique, hides the information in mathematical functions like compression
algorithms.

*** Steganography Tools

**** Steghide

To hide something in a picture using steghide we need to run the following
command:

#+begin_src bash
	steghide embed -ef [file_to_embed] -cf [container_file]
#+end_src

And to extract it we can run:

#+begin_src bash
	steghide extract -sf [stego_file]
#+end_src

**** Stegsnow

Snow adds tabs and spaces to a text file, to hide a message. It works like this:

#+begin_src bash
	stegsnow -C -m [message] -p [password] [input_file] [output_file]
#+end_src

And to extract the information we run the following command:

#+begin_src bash
	stegsnow -C -p [password] [file_with_information]
#+end_src
